This invention relates to propellant and explosive compositions based on mixtures of organic acids, potassium nitrate and potassium perchlorate useful for propellant and other pyro-technic and explosive applications.
Many combustible compositions having utility as gunpowder, explosives, propellants and other pyro-technic applications have been formulated and many of these compositions utilize organic or inorganic nitrates as an oxidizer in combination with an organic acid as a fuel. For example, ammonium nitrate and alkali metal nitrates are preferred oxidizers.
U.S. Pat. No. 4,497,676 to Kurtz discloses an aqueous slurry of an organic acid, such as ascorbic or erythorbic acid, and an inorganic nitrate such as potassium nitrate which, when heated to evaporate the water, produces an explosive composite material. The material is safer to handle than black powder and produces less noxious fumes but provides similar explosive and propellant performance.
U.S. Pat. No. 4,728,376 to Kurtz discloses an improvement in the above composition which is obtained by heating the mixture during processing to a temperature which produces a chemical or physical change in the organic acid.
In Patent Application WO 90/15788 to Kurtz, it is also disclosed that other oxidizing agents such as potassium perchlorate can be utilized however, there is no example of a composition in which potassium perchlorate is present.
It has also been shown that corrosivity of combustion residue and decrease in smoke production can be obtained by replacing the commonly used organic acids, ascorbic acid and erythorbic acid with the corresponding 5,6-carbonyl derivatives, namely 5,6-carbonyl ascorbic acid or 5,6-carbonyl erythorbic acid. (U.S. Pat. No. 4,881,993 to Finbinger).
It would be desirable to obtain propellant and explosive compositions that are easily and safely handled and which tend to burn predictably, yet completely, producing little smoke and little residue. It would also be desirable to be able to provide propellant and explosive compositions in which the time to peak pressure as well as the peak pressure may be easily adjusted for each particular end use, and, which are easy to produce and safe to handle. These objectives have been difficult to obtain in a single product due to the powerful and often unpredictable oxidizer activity of nitrate containing oxidizing agents.